Looks like it is either a bad ground wire, speed sensor, or ECBM:
There are two very common issues with these models that can cause those two lights to illuminate:1) faulty Electronic Control Module (EBCM) and 2) faulty wheel sensors.
The EBCM will set specific codes indicating an internal malfunction. This is often cause by either a poor ground situation on the drivers side frame rail, just under the drivers door and also caused by a faulty EBCM. If the EBCM is indeed faulty, it can be rebuilt. I have sent many to www.modulemasters.com for repair. They are affordable and quick.
If you have wheel speed sensor codes, we would need to know if they are performance codes or "circuit" codes. Performance codes indicate that the sensor has checked out electronically, but fails to give a valid signal. For performance codes, the sensors usually need cleaned. The tip of the sensor slides into a hole on the wheel hub assembly and the base of the sensor bolts to the outside of the hub. Rust and corrosion can build up under the sensor and push the sensor tip away from what it reads, causing low signal output. Removing the sensor from the hub, allows you to clean rust and corrosion from the sensor mounting surface restoring the factory clearance. You DO have to take the rotor and caliper off to perform this.
A "circuit" code indicates that the sensor has failed electronically and requires replacement. The procedure is the same as cleaning the sensor, only instead of re-installing the old sensor, you install a new one.
For either wheel speed sensor case, you will want to check the free play of the wheel bearing. There should be NO free play in the bearing, although a very little is acceptable. Excessive free-play can cause codes as the inner part of the bearing moves to and away from the sensor mounted to the outside of the bearing (hub).
Edited by jBlaze3000, 08 June 2012 - 12:37 PM.